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Observational Evidence Against Birefringence Over Cosmological Distances

J. F. C. Wardle·R. A. Perley·M. H. Cohen
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Abstract

We show that recent radio and optical observations of polarized radiation from well-resolved high redshift quasars and radio galaxies rule out the cosmological rotation of the plane of polarization claimed recently by Nodland and Ralston. A least squares fit to the radio data has a slope only 2% of their claimed effect.

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J. F. C. Wardle, R. A. Perley, M. H. Cohen. 1997-07-15. Observational Evidence Against Birefringence Over Cosmological Distances. https://doi.org/10.1103/physrevlett.79.1801

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